Cartridge-fuse.



A.-E.10HNS0N.

CARTRIDGE FUSE.

APPLICATON FILED DEC.20. i915.

3,266,599, Patented' May 21, 1918.

UNITED STATES PATENT oEEicE.

l linnn r. JomvsoN, or DENVER., comincio.Y

Specification of Letters Patent.

ppiimion niea'iieoember 2o, i915. serial ivo. 67,763.

clear, aid exact description of the invention, such as will enable ot ers skilled in the art to which it appertains to inake and -use the saine reference being had'to the accompanying drawin and to the characters of reference mar ed thereon, which form a part of this specification. be,

My invention relates to improvements in cartridge ',fuses, andone of my objects is to provide a device of this character simple and compact in construction, and one in which the fuse can be readily replaced without the aid ofl tools.

Another object of my invention is to divide the interior of the cartridge into two compartments b means of a partition, and

to locate aispira spring in one of said compartments and connect a fuse therewith in such a'manner that when an excess or overload of current is introduced the break in the fuse can take place in one coin artment only, and theimoment the said brea y occurs,

the portion of the fuse connected with thel said spring will instantly be drawn into the other com artment, whereby` the arc formed between t e broken extremities of the fuse will blquickly broken and the flame extin- Still another object of my' invention is to form a `frustumfshaped connection between several convolutions of `the spiral spring. and one extremity of the fuse, whereby the closest possible contact is formed between the said elements. v

Having brieiiy outlined my imgioved construction, I will proceed to descri the same in detail, reference being made to the accompanying drawing, in which is illustrated y an embodiment thereof. In this drawing,-'= v 'Figure 1 is a view of one of m improved Y cartridge fuses completely assem led.

Fig. 2 is an end view taken in the direction ofthe arrow 2, Fig. 1.

Fig. 3 is a similar view open for the insertion of the fuse'.

Fig. 4 is an end view taken in the direction of the arrow 4, Fig. l, showing one extremity of the fuse secured in position. I

Fig. 5 is a similar view with the fuse proand quickly.

showing the cap truding beyond one extremity of the cartridge but unattached thereto.

' Fig. 6 is a longitudinal view of the cartridge fuse taken on the line ,6-6, Fig. 1, looking in the direction of the arrow.

Patented May 21, 1918,.

Fig. 7 is a similar view showing the relav tion of the parts after the fuse is melted.

Fig. 8 is a similar section showing the fuse inserted in the cartridge but before it is secured under tension.

Fig. 9 is a detail view of the fuse which -I Iemploy.

The same reference characters indicate the same parts in all the views.

Let the numeral 5 designate a cylindrical shell or casing open at its extremities and com osed of rubber, fiber or other non-conducting material. Metallic caps 6 and 7 are respectively fitted over the opposite extremities of the shell, and are detachably connected therewith by means of bayonet joints 8. The cap 6 has a relatively large openin 4 while the cap 7 is provided with a sma er opening 9. A late 10 is ivotally mounted at 11 upon t ecap 6 adjacent the opening therethrough, and is adapted to cover or-uncover said opening as circumstances re uire.

The shetll 5 is provided interiorly with a partition 12 also composed of suitable insulating material, and which partition divides the interior of the said shell into two ed to be inserted into the shell through the opening 4 in the cap 6, said fuse .wire passing through the .frustum-shaped opening 15 in the partition 12 and the opening 9 in the cap 7, whereby it will 'project beyond the oppositeextremity of the said shell as lshown at 21. One extremity of this fuse is :formed -frustum-sha ed as disclosed at 22, and, therefore, w be retained within the spring 16, the surface of the frustum-shaped portion of said fuse closely engaging the con` volutions of the spring 16 forming the frustum-shaped extremity 19. By virtue of no l the corresponding shape of the extremitiesl of the fuse wire and the spring when the latter is distended, the closest possible consembled as disclosedupon Fig. 8 of the drawing, the extremity 21 of the fuse is grasped and pulled outwardly whereby7 the spring 16 is distended or expanded until its inner or frustumshaped extremity engages the partition 12 which will permit lthe enlarged portion 23 of .the fuse to pass through the opening 15 in the said partition and project slightly into the compartment 14, after which the .extremity 21 of the fuse is wound around the pins or buttons 24, secured exteriorly to the cap 7 (see Fig. 4). The cartridge is then ready for use Aas disclosed in Figs. 1 and 6, and its metal capped extremities are inserted into contact clips (not shown) in the usual manner, whereby the current will pass from one pair of said clips through the cap 6, the spring 16, the fuse 20, the pins or buttons 24, and the cap 7 tothe other contact clips, thereby com pleting the circuit. v

1f the current is increased to such an extent that it will melt thefuse, the break will occur in the compartment 14 and forward of the enlarged portion 23 of thefuse, since naturally the smaller portion of the latter partition.

will melt rst, and the instant the said fuse is broken thespring 16 will be released and jerk the portion of the fuse connected therewith through the opening 15 in the partition 12 and into the compartment 13, whereby the are formed between the extremities of the fuse will be quickly broken vand prevented.

from reforming by virtue of the intervening The cap 6 1s then detached from the shell, whereby the end of the fuse connected with the spring can easily be removed by pushing,

it through the spring and the opening in the cap 6.

In order to detach the other portion of the fuse it is only necessary to unwind it from the pins or'buttons 24 when it can be readily withdrawn through the opening 9 in the cap 7. The cap 6 is then again applied to the shell and a new fuse substituted by inserting the same through the opening 4 in the cap 6 as heretofore explained. v

.Attention is called to the fact that the pivotally 'mounted plate 10 at ell times covers the opening 4 through the cap 6 except when a new fuse is being substituted for a broken one.

From the foregoing description it will be y readily understood that a broken fuse can be removed from the cartridge and a rnew fuse substituted without the employment of any tools whatever.

Having thus described invention, what` rated cap adjacent said spring to enter the large end of the spring and provided with an end portion adapted to engage the opposite end of the spring which is also formed frustum-shaped, whereby a close-contact is formed, the said fuse extending through the opening in the partition and the perforationin the other cap, and means mounted upon the last named cap and around which the other end of the fuse is adapted to be wound.

2. A cartridge fuse comprising a cylin drical casing, a partition'located within said casing and provided with an opening, perforated metallic caps detachably applied to the opposite extremities` of said casing, a.

spiral spring secured at one extremity to one l of said caps and its opposite extremity being wound frustum-shaped, a fuse one end of which is secured within the frustum-shaped extremity of the spring, said end of the fuse being also formed frustum-shaped to conform, to the interior of said spring, the said fuse extending through the opening in the partition and the perforation in the other cap, and means mounted upon the last named cap to which the other end of the fuse is adapted to be attached. y,

3.,A cartridge fuse comprising a casing, electrical contacts removably provided at the extremities of said casing, a frustumshaped-coiled spring within said casing, and connected to one end thereof, the end of the casing having the spring attached thereto being provided with an opening, and a removable fuse adapted to be inserted in said opening and enter the large end of said frustum-shaped spring, said fuse having a conical end part coperating with the small.

jacent-said spring, to enter the large portion of said spring, said fuse having an end portion engaging the small end of said spring and means for securing said fuse at the opposite end of the casing.

k5. A fuse comprising a casing, an open parl vtition located in the latter and dividing it into two compartments, metallic caps provided with openings and detachably applied to the opposite extremities of said casing, a

sp g located in one of said compartments and secured to one of said caps, a fuse attached to said spring and having an enlar ed portion adjacent said connection, said se extending through both compartments, the

opening in the other cap and beyond the latter, whereby the spring may be distended until it engages the partition and said enlarged portion of the fuse projects slightly into the other compartment, and means mounted exteriorly upon the last named cap to which the fuse is also vadapted to bev attached for holding the spring and fuse in their operative positions.

In testimon whereof I aiiix my signature, in presence oy two witnesses.

, ALFRED E. JOHNSON. Witnesses:

Guen HUsToN, i ALBERT OBRIEN. 

